[Distutils] Adding entry points into Distutils ?

[Doug Hellmann]

On May 5, 2009, at 11:05 AM, Tarek Ziadé wrote:

> On Tue, May 5, 2009 at 4:29 PM, Doug Hellmann  
> <doug.hellmann at gmail.com> wrote
>>
>>> a configuration file that reunites all entry points an application
>>> uses. For the Atomisator example:
>>>
>>>  [atomisator.reader]
>>>  rss = somepackage.somemodule:MyPluginClass
>>
>> Yes!  We can figure out the exact spelling, but we're talking about  
>> the same
>> thing now.  If we use dotted notation all the way
>> ("somepackage.somemodule.MyPluginClass") then it's simple to just  
>> import the
>> thing directly.
>
> I think is simpler with the "somepackage.somemodule:MyPluginClass"  
> notation

Good point, I was remembering the import syntax incorrectly.

>>> And this would fit I think in Distutils needs since we can configure
>>> it through three levels of configuration files
>>> distutils.cfg, pydistutils.cfg and setup.cfg
>>
>> That sounds good.
>
> The only caveat I see though, is that the host app has to know the
> exact location
> of each plugin in the code of the third party app, whereas entry  
> points provide
> this information through the discovery API.

True.  On the other hand, that encourages standard locations like  
"mylib.yourapp.entry_point" and "mylib.anotherapp.entry_point".

I think most of my concerns about the global registry are taken care  
of by the fact that "discovering" a plugin doesn't involve any imports  
of unknown code.  I still prefer per-app, explicit configuration of  
entry points, and think we could build a system to support that.  I  
would like to see *some* variation of this in the standard library,  
though, because I have several uses for it.

Doug